Electromagnetic Wave Propagation In Time-dependent Magneto-electric Medium

In recent years, the magneto-electric media becomes an important field, which was originally proposed by Landau, later verified by experiment with Cr2O3. Now it gets much developed and applied including BFO materials. Theoretically, time-dependent magneto-electric media plays an important role in dealing with the axion electrodynamics and topological surface states.In this paper, the phenomenon of light propagation through time-dependent media without charge density and current is studied. When the coefficient ??t? 、 ??t? changed with the time, the frequency of electromagnetic wave will be changed. What is more, a quantum description is presented, by the dynamical invariant method(LR) in the framework of the Schr?dinger equation. We obtain the corresponding exact wave functions which can be considered as the function of the amplitude of the classical damped and time-dependent harmonic oscillator. In addition, we calculate the uncertainty products for particular quantized states of electromagnetic field in time-dependent media.A study of light propagation through time-dependent magneto-electric media without charge density and current is also presented, by the dynamical invariant method in the framework of the Schr?dinger equation. The new physical phenomenon is obtained because of magneto-electric coefficient ??t?. On classical level, the pair of TCB modes can appear simultaneously via the “time refraction” and “time reflection” of a linearly polarized incident wave at a time-discontinuous interface of the ME media. The superposition of two TCB modes causes the “time Faraday effect” which is a novel effect as a temporal counterpart of the ordinary spatial Faraday effect or optical activity. On quantum level, we also obtain the corresponding exact wave functions which can be considered as the function of the amplitude of the classical damped and time-dependent harmonic oscillator. In addition, we show that the particular quantized states of electromagnetic field in time-dependent magneto-electric media is changed over the time rate ? change of the magneto-electric coefficient ??t?. At last, we explain the corresponding physical meaning.